Boiler safeties

1.  Safety valve
2. Pressure gauge
3. Easing gear
4. Air vent
5. Water level indicators (Boiler control panel & ECR panel)
6. Boiler gauge glass
7. Low water level alarm
8. Low low water level alarm and shut down (Trip)
9. High water level alarm
10. Low F.O pressure alarm
11. Low F.O temperature alarm (Trip)
12. High F.O temperature alarm (Trip)
13. Low steam drum pressure alarm 
14. High steam drum pressure alarm (Trip)
15. Forced draught fan stop alarm
16. Flame failure alarm
17. Smoke density high alarm 

Note: surveyor will ask what are alarms and what are trips 

Air Compressor Safeties

1. Drain valve
2. Unloader 
3. Bursting Disc (Copper disc) 
4. Fusible plug (50% Bi, 30% Tin, 20% Pb)
5. Relief valve
6. L.O low pressure alarm and trip
7. Jacket Cooling water High temperature trip
8. Jacket water no-flow trip
9. High air temperature trip
10. Motor overload trip

Start Air Line Safeties

1. Flame trap (at joint where manifold to each cylinder starting line)
2. Bursting disc cap or relief valve
3. Automatic shut-off master valve
4. Non-return start air valves
5. Drain cock in the manifold and at other parts
6. Drain cock before shut-off valve
7. Temperature sensors and pressure gauges
8.  Running direction and turning gear engaged interlocks to prevent accidental starting

Main Engine Safeties

1. Overspeed trip 
2. Emergency manual trip
3. L.O low pressure trip
4. Camshaft L.O low pressure trip
5. Thrust bearing high temperature trip
6. Main bearing high temperature trip
7. JCW low pressure slow down alarm
8. Piston cooling water low pressure slow down alarm
9. Main engine fuel leak tank alarm 
10. Sump oil level low alarm
11. Spring air pressure low with starting air valve system line.
12. OMD-alarm 
13. Scavenge fire alarm  

Auxiliary Engine Safeties

1. Thermometer
2. Pressure gauge
3. Dip stick
4. crankcase door relief valve
5. cylinder head relief valve
6. F.O low pressure alarm
7. L.O low pressure alarm and trip
8. L.O high temperature alarm
9. Cooling F.W high temperature alarm
10. Cooling F.W low pressure trip
11. Fuel leak tank alarm
12. Starting air pressure low alarm
13. Exhaust gas high temperature alarm 
14. Windings high temperature alarm
15. Pedestal bearing high temperature alarm
16. Overspeed trip
17. Reverse power relay

Main Engine Auto slow down reasons

Main Engine (Auto Slowdown)

1. Oil mist high density
2. Scavenge air box fire
3. Main L.O low pressure
4. Cylinder cooling F.W low pressure
5. Cylinder L.O non-flow
6. Cylinder cooling F.W high temperature
7. Piston cooling oil high temperature
8. Stern tube bearing high temperature 
9. Thrust bearing segment high temperature
10. Exhaust gas outlet high temperature/high deviation
11. Exhaust Gas Economizer high temperature
12. Exhaust Gas Economizer water non-flow